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 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://github.com/payara/Payara/blob/main/LICENSE.txt
 * See the License for the specific
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 * file and include the License file at legal/OPEN-SOURCE-LICENSE.txt.
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 * GPL Classpath Exception:
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 * file that accompanied this code.
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package fish.payara.jdbc.stats;

import com.sun.gjc.util.SQLTrace;
import java.util.Comparator;

/**
 * Extends the SQLTrace class to also store the slowest SQL execution times.
 * @author Andrew Pielage
 */
public class SlowSqlTrace extends SQLTrace {
    
    private long slowestExecutionTime;
    
    public SlowSqlTrace(String query, int numExecutions, long time, long executionTime) {
        super(query, numExecutions, time);
        this.slowestExecutionTime = executionTime;
    }
    
    /**
     * Gets the slowest execution time for this SQL Trace
     * @return The slowest execution time
     */
    public long getSlowestExecutionTime() {
        return slowestExecutionTime;
    }
    
    /**
     * Sets the slowest execution time for this SQL trace
     * @param slowestExecutionTime The execution time to set
     */
    public void setSlowestExecutionTime(long slowestExecutionTime) {
        this.slowestExecutionTime = slowestExecutionTime;
    }
    
    // Comparator that orders based on the slowest execution time, the number of executions, and the last usage time.
    public static Comparator<SlowSqlTrace> SlowSqlTraceSlowestExecutionComparator = new Comparator<SlowSqlTrace>() {
        
        @Override
        public int compare(SlowSqlTrace sqlTrace1, SlowSqlTrace sqlTrace2) {
            final long sqlTrace1SlowestExecution = sqlTrace1.getSlowestExecutionTime();
            final long sqlTrace2SlowestExecution = sqlTrace2.getSlowestExecutionTime();
            
            // Initialise the comparison variable to be equal
            int compare = 0;
            
            // Compare the execution times
            if (sqlTrace1SlowestExecution < sqlTrace2SlowestExecution) {
                compare = 1;
            } else if (sqlTrace1SlowestExecution > sqlTrace2SlowestExecution) {
                compare = -1;
            }
            
            // If the execution times are equal, compare against the number of executions
            if (compare == 0) {
                final int sqlTrace1Frequency = sqlTrace1.getNumExecutions();
                final int sqlTrace2Frequency = sqlTrace2.getNumExecutions();
                
                if (sqlTrace1Frequency < sqlTrace2Frequency) {
                    compare = 1;
                } else if (sqlTrace1Frequency > sqlTrace2Frequency) {
                    compare = -1;
                }
                
                // If the number of executions is also the same, compare the last usage times
                if (compare == 0) {
                    final long sqlTrace1LastUsageTime = sqlTrace1.getLastUsageTime();
                    final long sqlTrace2LastUsageTime = sqlTrace2.getLastUsageTime();
                    
                    if (sqlTrace1LastUsageTime < sqlTrace2LastUsageTime) {
                        compare = 1;
                    } else if (sqlTrace1LastUsageTime > sqlTrace2LastUsageTime) {
                        compare = -1;
                    }
                }
            }
            
            return compare;
        }
    };
}
